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"Colossal Magnetic Effect" Could Lead To Another Breakthrough In Storage Tech
Bryant writes "Scientists with the Carnegie Institution for Science have discovered what could bring yet another massive advance in memory and storage. The discovery, a magnetoresistence literally 'up to 1000 times more powerful' than the Giant Magnetoresistence Effect discovered roughly 20 years ago, which led to one of the major breakthroughs in memory, seems to be a result of high-pressure interactions between Manganites. Manganites aren't new to this game; MRAM uses Manganite layers to achieve the Magnetic Tunnel Effect needed to keep the state of memory stable. Applying significant amounts of pressure to known tech-useful materials isn't a new trick; you might recall the recent breakthrough with Europium superconductivity thanks to similar high-pressure antics."
It's a combination of persistence, random I/O and storage actually.
SSDs are good at the first two, but still have catching up to do on the latter (and price...), but as soon as a reasonably priced 1TB version comes out, that'll be a great boon...
Though I do agree that SSD's are definitely the next big thing when it comes to computer performance, there are a lot of things that need to happen before they become the definitive standard in storage. As you mention, the price/GB ratio needs to come down, but in addition to that:
- SATA 3 needs to come out. Though most SSD's don't exceed SATA 2 bus speeds, higher end SSD's like the OCZ Vertex or Intels X-25m hit 250MB/s sustained speeds. ONFi (open nand flash alliance? something like that) recently announced what is essentially the NAND 2.0 standard which doubles the speed of NAND modules, meaning next generation SSD's could easily hit sustained speeds of 500MB/s without any special tricks like internal raid. SSD's are already faster, but for better futureproof-ness and the ability to get the full potential out of SSD's, bus speeds need to increase quite a bit.
- TRIM needs to get at more OS's and SSD's support. SSD's write performance degrades with use due to a combination of the mechanics of NAND flash itself and common wear leveling algorithms. Essentially what happens is that when reading the flash blocks, all the SSD has to do is pass over and read the data. When writing though, if the block was previously written to the SSD has to erase the entire block clean and *then* write it. This is further exacerbated on MLC SSD's, where the individual transistors each store 2 bits, which on average doubles the write time with the benefit of double the space for the same price (instead of 0 or 1 like a SLC SSD, each one stores either 00, 01, 10, or 11). TRIM effectively eliminates a step from the write process on a previously used SSD by erasing blocks marked as free by the OS during an idle period, which means that write speeds degrade less over time.
- Manufacturing processes need to mature, as well as firmwares, wear-leveling algorithms, and filesystems. Unlike platter hard drives SSD's don't have decades of optimization and experience, which means higher than acceptable failure rates, extra consumer knowledge required to properly install and maintain, OS tweaks needed to fully exploit the current capabilities of SSD's, and certain technologies just not being available yet (a recent ext4 v btrfs SSD comparison on phoronix showed that btrfs was much much slower than ext4 despite the potential for btrfs to be better optimized for SSD's).
My personal belief is that by the time SSD's are halfway done with all of the above (including price/GB), they will overtake traditional HDD's in the market. The advantages of SSD's are already here and apparent, they are just expensive and a relatively young technology with a few growing pains. By the time the growing pains are half resolved SSD's will be much superior in just about every way possible, and then they will really really take off.
When I did a presentation on hard drives 3 years ago, I had already read some things saying that the Colossal Magnetorsestive Effect was the next step in read-write head technology. The Wikipedia page says the effect was discovered in 1993. This new discovery might make it more feasible, but hard drive technology developers already knew that CMR would be a part of the technology going forward.
Software sucks. Open Source sucks less.
This is not new, nor truly preliminary technology; I researched this back in 2004 and there was already a huge amount in the literature. It's just an incremental improvement and uses by and large existing thin film technologies pushed to their limit.
Most people didn't even notice the transition from regular magnetorestrictive heads to giant magnetoresistive heads, they were just incorporated naturally so that hard drive densities could further increase. This technology is the obvious and natural extension from giant magnetoresistive heads, and the increased signal to noise ratio will allow for denser drives with no doubt -- although we're already at the point where a "bit" is only made up of a few dozen magnetic domains. But in any case, this type of technology is a prerequisite for using more highly nanocrystalline magnetic materials with smaller domains...